I'm trying to learn to load apps on my iPhone from Xcode. When I do I keep getting "Codesign wants to access key "access" in your keychain, I put I my login password but it keeps popping up over and over. I've tried my computer login so many times, apple account password, and many others.

One or More dialogs opened and positioned in the same dialog, repeat step 1 until all dialogs closed. (So you thought your
password wrong but repeat "Always Allow" with your Mac login
password tricky part :) )

I encountered this running a brand new project. Neither the Allow or Always Allow button seemed to work, however it wasn't giving me the 'incorrect password' shaking feedback. What was happening was that there were multiple dialog boxes all in the same position, so as I entered a password and clicked Allow nothing changed visually. I ended up having at least 3 dialogs all stacked up on each other, which I only discovered when I tried dragging the dialog. Entering passwords into each of them let my project finish building.

Same thing happened to me, saw it because the shadow around the dialog was a lot more visible than normal. When uploading the app I did get another 2 dialogs. It seems okay now. Oh Xcode...
– EricH206Jan 4 '18 at 15:17

@Green The answers by Bharathi Devarasu (the answer currently below this answer) and Anton Eregin (answer above) describe what password this dialog is asking for. However, in some cases the keychain password may not be the same as your mac user's password. If you've forgotten your keychain password, you can reset it. Perhaps try the answers here: stackoverflow.com/questions/50928239/…
– AriJul 9 '18 at 20:27

I love this. Before, maybe xcode 8 and below, I had been trying to script allowing access to something like /Applications/Xcode.app/Contents/Developer/usr/bin/codesign , but since xcode9 that path does not exist. Any tool would be inside the parent .app so this is very good. :cross-fingers: for no more issues!
– AnneTheAgileDec 13 '18 at 22:13

I was also having the problem while running the carthage script in the build phase. (Xcode 9)
I get that dialog for each and every framework I had added plus the app itself. You can see a very dark shadow growing.
I could bypass it by entering the password every time and hitting "Always Allow".